[MAJOR] Added a simple device tree parser

minix/include/minix/board.h

@@ -168,7 +168,6 @@ struct shortname2id
 	unsigned int id;
 };
 
-
 /* mapping from fields given by the bootloader to board id's */
 static struct shortname2id shortname2id[] = {
 	{.name = "BBXM",.id = BOARD_ID_BBXM},
@@ -178,6 +177,21 @@ static struct shortname2id shortname2id[] = {
 	{.name = "RPI_3_B",.id = BOARD_ID_RPI_3_B},
 };
 
+struct longname2id
+{
+	const char name[40];
+	unsigned int id;
+};
+
+/* mapping from fields given by the device tree to board id's */
+static struct longname2id longname2id[] = {
+	{.name = "BBXM",.id = BOARD_ID_BBXM},
+	{.name = "A335BONE",.id = BOARD_ID_BBW},
+	{.name = "A335BNLT",.id = BOARD_ID_BBB},
+	{.name = "Raspberry Pi 2 Model B Rev 1.1",.id = BOARD_ID_RPI_2_B},
+	{.name = "Raspberry Pi 3 Model B Rev 1.2",.id = BOARD_ID_RPI_3_B},
+};
+
 struct board_id2name
 {
 	unsigned int id;
@@ -218,6 +232,19 @@ get_board_id_by_short_name(const char *name)
 	return 0;
 }
 
+/* returns 0 if no board was found that match that id */
+static int
+get_board_id_by_long_name(const char *name)
+{
+	int x;
+	for (x = 0; x < sizeof(longname2id) / sizeof(longname2id[0]); x++) {
+		if (strncmp(name, longname2id[x].name, 15) == 0) {
+			return longname2id[x].id;
+		}
+	}
+	return 0;
+}
+
 /* returns 0 if no board was found that match that id */
 static int
 get_board_id_by_name(const char *name)

minix/kernel/arch/earm/Makefile.inc

@@ -28,7 +28,7 @@ CLEANFILES+= ${ORIG_UNPAGED_OBJS}
 SRCS+=	mpx.S arch_clock.c arch_do_vmctl.c arch_system.c do_padconf.c \
 	exception.c hw_intr.c klib.S memory.c pre_init.c \
 	protect.c direct_tty_utils.c arch_reset.c \
-	pg_utils.c phys_copy.S phys_memset.S exc.S
+	pg_utils.c fdt.c phys_copy.S phys_memset.S exc.S
 
 OBJS.kernel+=	${UNPAGED_OBJS}
 

minix/kernel/arch/earm/fdt.c

@@ -0,0 +1,47 @@
+#include <libfdt.h>
+#include <minix/board.h>
+#include <minix/type.h>
+#include "fdt.h"
+
+void *dev_tree;
+
+int fdt_set_machine_type (void *fdt, int offset, void *dst)
+{
+	struct machine *machine = (struct machine *)dst;
+	const char *model = fdt_getprop(fdt, offset, "model", NULL);
+	if (model == NULL)
+		return -1;
+		
+	machine->board_id = get_board_id_by_long_name(model);
+
+	if (machine->board_id == 0) {
+		/* same thing as above there is no safe escape */
+		return -1;
+	}
+	return 0;
+}
+
+int fdt_set_memory (void *fdt, int offset, void *dst)
+{
+	return 0;
+}
+
+int fdt_set_cpu_num (void *fdt, int offset, void *dst)
+{
+	return 0;
+}
+
+int fdt_step_node (void *fdt, int (*cb)(void *fdt, int offset, void *dst), void *dst)
+{
+	int offset = -1;
+	int len = -1;
+	int retv = 0;
+	for (offset = fdt_next_node(fdt, -1, &len);
+		 offset >= 0 && len >= 0;
+		 offset = fdt_next_node(fdt, offset, &len)) {
+		retv = cb(fdt, offset, dst);
+		if (retv == 0)
+			return 0;
+	}
+	return -1;
+}

minix/kernel/arch/earm/head.S

@@ -130,7 +130,7 @@ check2:
 	orr r3, r3, #ARM_VM_SECTION_USER
 	orr r3, r3, #ARM_VM_SECTION_DOMAIN
 1:
-	ldr r5, =0x3effffff //FIXME
+	ldr r5, =0x3effffff
 	cmp r7, r5
 	blo cached
 	ldr r2, =#ARM_VM_SECTION_DEVICE
@@ -154,7 +154,7 @@ setup:
 /* The first free entry in the page table is placed	*/
 /* in freepde.										*/
 /****************************************************/
-	ldr	r6, =0xf0400000 //FIXME
+	ldr	r6, =_kern_vir_base
 	mov r7, r9
 	add	r5, r4, r6, lsr #18
 
@@ -228,11 +228,10 @@ setup:
 
 	mov r2, r10
 	ldr	sp, =k_initial_stktop	/* make usable stack */
-
 	mov r3, #0
 	push {r3}
 	mov	fp, #0
-	push	{r3}	
+	push	{r2}	
 	bl _C_LABEL(pre_init)
 
 	ldr r4, =1384 // FIXME
@@ -240,15 +239,15 @@ setup:
 	ldr r5, =freepde
 	ldr r5, [r5]
 	str r5, [r3]
-
+	pop {r2}
 	/* Kernel is mapped high now and ready to go, with
 	 * the boot info pointer returned by pre_init in r0.
 	 * Set the highly mapped stack and initialize it.
 	 *
 	 * After that call kmain with r0 still pointing to boot info
 	 */
-	ldr	r2, =_C_LABEL(kmain)	/* r0 holds kinfo_t ptr */
-	bx	r2
+	ldr	r3, =_C_LABEL(kmain)	/* r0 holds kinfo_t ptr */
+	bx	r3
 
 	/* not reached */
 hang:

minix/kernel/arch/earm/include/fdt.h

@@ -0,0 +1,9 @@
+#ifndef __FDT_H__
+#define __FDT_H__
+
+int fdt_set_machine_type (void *fdt, int offset, void *machine);
+int fdt_set_memory (void *fdt, int offset, void *dst);
+int fdt_set_cpu_num (void *fdt, int offset, void *dst);
+int fdt_step_node (void *fdt, int (*cb)(void *fdt, int offset, void *dst), void *dst);
+
+#endif

minix/kernel/arch/earm/pre_init.c

@@ -16,9 +16,8 @@
 #include "bsp_table.h"
 #include "glo.h"
 #include <machine/multiboot.h>
-
 #include <libfdt.h>
-#include <libfdt_internal.h>
+#include "fdt.h"
 
 #if USE_SYSDEBUG
 #define MULTIBOOT_VERBOSE 1
@@ -40,6 +39,8 @@ int kernel_may_alloc = 1;
 extern u32_t _edata;
 extern u32_t _end;
 
+extern void *dev_tree;
+
 #define BSP_TABLE_GENERATE(name) \
 	do { \
 		platform_tb.bsp_init = name##_init; \
@@ -416,43 +417,6 @@ void set_bsp_table()
 	bsp_tb = &platform_tb;
 }
 
-static void test_node(const void *fdt, int parent_offset)
-{
-	uint32_t subnodes;
-	const fdt32_t *prop;
-	int offset;
-	int count;
-	int len;
-	/* This property indicates the number of subnodes to expect */
-	prop = fdt_getprop(fdt, parent_offset, "subnodes", &len);
-	if (!prop || len != sizeof(fdt32_t)) {
-		printf("Missing/invalid subnodes property at '%s'",
-		fdt_get_name(fdt, parent_offset, NULL));
-	}
-	subnodes = fdt32_to_cpu(*prop);
-	count = 0;
-	fdt_for_each_subnode(offset, fdt, parent_offset)
-	count++;
-	if (count != subnodes) {
-		printf("Node '%s': Expected %d subnodes, got %d\n",
-	    	fdt_get_name(fdt, parent_offset, NULL), subnodes, count);
-	}
-}
-
-void parse_dev_tree(const void *dev_tree)
-{
-	uint32_t offset;
-	uint32_t len;
-	if (!fdt_check_header(dev_tree)) {
-		printf("BAD HEADER\n");
-		return;
-	}
-	int node;
-	fdt_for_each_subnode(node, dev_tree, 0) {
-		test_node(dev_tree, node);
-	}
-}
-
 void read_tsc_64(u64_t * t) 
 {
 	bsp_tb->read_tsc_64(t);
@@ -471,9 +435,7 @@ int intr_init(const int auto_eoi)
 kinfo_t *pre_init(int argc, char **argv)
 {
 	char* bootargs;
-
-	void* dev_tree;
-	asm volatile ("ldr %0, [%%r2]":"=r"(dev_tree)::"r2", "memory");
+	asm volatile ("mov %0, r2":"=r"(dev_tree)::"r2", "memory");
 
 	/* This is the main "c" entry point into the kernel. It gets called
 	from head.S */
@@ -486,8 +448,11 @@ kinfo_t *pre_init(int argc, char **argv)
 		POORMANS_FAILURE_NOTIFICATION;
 	}
 
-	bootargs = argv[1];
-	set_machine_id(bootargs);
+	if (fdt_step_node(dev_tree, fdt_set_machine_type, &machine)) {
+		bootargs = argv[1];
+		set_machine_id(bootargs);
+	}
+
 	set_bsp_table();
 
 	/* Get our own copy boot params pointed to by r1.